Radio receiving system



Nov. 3 1925. 1,559,743

- H. J. J. M. DE R. DE BELLESCl-ZE RADIO RECEIVING SYSTEM Filed Aug. 29, 1921 2 Shet's-Sheet i Sammie;

w. u. m, De BELLESICIZE ggwhis- Jm/WM To all whom it-mciy concern:

Patented Nov. 3, .1925.

, 1,559,743] UNITED s'umzs PATENT OFFICE.

HENRI J EAN JOSEPH MARIE DE nnoimonn 1m BEnLnscIzE, onranrs, nuance.

namo nncnrvinc SYSTEM.

Application filed August 28, 1921. Serial No. 496,533.

Be it known that I, HENRI J. J. M. DE R. DE BELLEsc zE, a citizen of France, and resident of Paris, France, have invented certain new and useful Improvements in Radio Receiving Systems, of which the following is a specification, accompanied by drawings.

lows:

The invention is an improvement over the .one shown in my French Patent 506,142 and corresponding U. S. application No. 318,369 filed August 18, 1919. r

The object of the present invention is- (1) To remedy a practical difficulty encountered in connection with. the system therein described.

(2) To extend theprinciple of the protection to the reception of continuous waves without a heterodyne.

The circuit arrangement .of Fig. 1 comprises two distinct receivers (l-2 and 11 12) each of which contains the same elements, and one receiver has no reaction on the other. One of the receivers is tuned to the wave that is to be received and the other receiver is detuned. Each receiver comprises a detector (3 4 and 13-14) which rectifies the oscillations.

The detected currents d-iflierentially energize one and the same low frequency circuit (20) which'in turn actuates the telephone 23) This circuit arrangement may be used or-receiving signals of modulated -amplitude (musical waves orcontinuous waves re- 'celved by means of the heterodyne wireless telephone signals, etc.).

The

The oscillation generated by the signal is i greater in the tuned than in the detuned receiver. The effect of one is therefore greater than that of-the other and their oppositionpermits a sound to occur in the telephone.

On the other hand, a. sudden disturbance Z acting like a shock generates in both receivers oscillations of the same amplitude giving rise .to detected currents of equal.

by opposition.

The difliculty to be. remedied is a follows:

strength which mutually destroy each other In order to obtain satisfactory function-- ing, it is necessary that none of the high frequency resonators constituting one of the receivers" react appreciably on any one of the resonators constituting thesecond receiver. 1 Thislresult may be secured by the use'of two distinctopen antennae or two principle of the operation is a fol closed circuit frames, the connection of one opposing that of the other. The latter necessitates the insertion between each frame and the corresponding detector of a powerful high frequen'cyamplifier. Experience shows that 'in' practice it is very difficultt6 obtain two amplifiers composed of numerous stages that behave always in indentically the same manner in response to disturbing noises the amplitude of. which is essentially variable. As a result of this, the. opposing effect obtained by a circuit arrangemenfiusing amplifiers is not always perfect.

According to the present invention, this disadvantage is avoided by eliminating the amplification between the two resonators and the corresponding detectors and by preceding the resonators by a highly damped amplifier, the function of this amplifierbeing to increase to a suflicient value the amplitude of the waves to be received and at the same time preservethe aperiodic charactor of the disturbances.

The invention is illustrated, by way of example, in the figures of drawlng, in which:

' Fig. 1, shows one arrangement according to the invention,

Fig. 2, a modification thereof, and

the accompanying Fig. 3, a detail of a modification of the an, aperiodic am lifier is inserted betweenthe antenna and t e resonators. The connection between the collector and the two 2) is i groups of high frequency resonators is arranged in a manner to avoid the introduction of any important reaction between these two.

The clrcuit arrangement of Fig. 1 has been intentionally-grouped'in a manner to reproduce below the dotted line'the arrangement of the basic circuit. collector is slioxyn above the dotted line. It consists of the antenna (3377-32-36) two vacuum tube relays (34.) each. energizing one of the be seen that, there is no possible reaction be- ;tween these two' groups 1f the coils 12 and and groups of high frequency. resonators, (1 2 and 1112). Thus it will The aperiodic 1-112 are positioned in the proper dire? tion, which may be easily accomplished. Fig. 2 shows a simplified circuit arrange ment comprising: the aperiodic antenna (33-32-36); an aperiodic amplifier (40- 41 J-42 43), a single vacuum tube rela (34) connecting the collector to the two hig frequency resonators-(1 and 11),,on'e being tuned to thewave to be received an,

and 13-44) for each resonator andtwo transformers and 15) to effect opposition in'the telephone 23.

The circuit arrangements shown in Figs. 1 and 2 are adapted for the reception of musical signals, heterodyne signals, or signalsmodulated as in wireless telephony. v The second object of the invention is to extend the principle of the protection against disturbances to the reception ofjcon tinous waves without heterodyne reception.

If very long waves are received, the damped oscillations created in the two groups of resonators (1, 2, 11, 12) by the shock of 'a disturbance, attain a suflicient duration so that they will interfere with the heterodyne and will cause vibrations that cannot be completely eliminated by means of the opposition effect. It will be advisable to do away with the heterodyne and to replace (see Fig.2) that part of" the circuit that is con'nectedtothe terminals d 1?, d

. by the arrangement shown in Fig. 3.

This arrangement is analogous to the one' described in the patent of the addition filed in France on December 13, 1920, No. 13,856 entitled Difierential circuit arrangement is to modify the interior resistance of. the

tube between the plate and the' filament.

, This resistance constitutes one of the branches of a Wheatstoneabridge the other branches of which, are. formed by-the' ad- [justable resistances 27, 28 and 29. The battery is connected into one of the diagonals of the bridge and the telephone 23 in series with the vibrator or ticket 22 in the other diagonal. It will be seen that the tele hone does not give any sound when the bri ge is balanced, i. 'e. when the potential drops are equal in the resistancesti and 16 (normal position for disturbances), and'that the telephone will be' operated under the control J of a signal which destroys the balance of the bridge. The difierence of the ohmic drop in d the other detuned; a vacuum tube detector (3-4 the resistances 6 and 16 affects the grid of.

tube 26, not directly but through the agency ofa strong self induction coil 24, (about 1 henry) connected in series with "aglarge capacity 25, (about 1 microfarad). Due to this .arrangement, ,high frequency oscillations which may become superposed on the detected currents can have no access to the tube Itshould be understood that the different figures and the above description are only for the purpose of illustrating the invention and may be modified in alarge number of ways without departing from the spirit of the invention.

Having described, my invention}, whatI I claim is:

1. In a. system for eliminating disturbances in receiving radio signals, the combination of an aperiodic antenna, indicating means, a tuned'and detuned. receiver associated with the aperiodic'antennmsaid receivers being differentially associated with the indicating means.

. 2. In a system for eliminating-disturbances 1n recelvmg radio signals, the com blnation -of aperiodic [collect1ngmeans, m-

dicating means, a tuned and adetuned receiver coupled to the collecting means, associated with the indicating means with their other.-

3111 a system for eliminating disturbancesqin receiving radio signals, the combin-ation-of aperiodic collecting means, in-- dicating means, a tuned and a detun-ed reeffects in opposition thereon and substantially noriinductively associated with each ceiver coupled to the collecting means and associated with the indicating means with their effects in opposition thereon and ape riodic amplifying means between said col- J lecting means and each of said receivers.

akin a system for eliminating-disturbances 1n receivin radio slgnals, the com 'bination of aperiodic collecting means, a

tuned and a detuned receiver coupled to the antenna, a detector circuit associated with each of said receivers and an indicator @359",

ciated'with each. of said detector circuitswith their efiects in' opposition.

5.111 a system for eliminating disturbances in receiving radio signals, the combination of an aperiodic antenna, an aperiodic amplifier, a relay coupled thereto, a pair of receivers coupled to the output of said relay, one of said receivers being tuned and the other detuned, a rectifier connected to each of said last mentioned circuits and indicating means difi'erentially coupled'to the output of each of said rectifiers.

6. In a system for eliminating disturbances in receiving radio signals, the combi-' nation of aperiodic collecting means, a rea Y ceiver resonant to the signal frequency and a receiver nonresonantto the signal frequency associated with the collecting means, a rectifier differentially connected to said receivers and an interrupter eonnegted to the output of said rectifier.

7 Inra system for eliminating disturbances in receiving radio signals, the combination of aperiodic collecting means, a re-' ceiver resonant .to the signal frequency and a receiver nonresonant to the signal frequency,impedances-connected to each of said receivers, a detector differentially associated with said impedances and means for interrupting the output of said detector at an audible frequency. p

8. In a radio receiving system the combinati'on of collecting means, a receiver resonant to signal frequency and a receiver non-resonant to signal frequency, impedances connected to each of said receivers, a rectifier differentially associated 'with said impedances and means for interrupting the output of said rectifier, said means comprising a three electrode tube having its input circuit associated with said rectifier and an interrupter connected in its output circuit.

9. In a radio receiving system the combination of collecting means, a receiver resonant to slgnal frequency and a. receiver non-resonant to signal frequency, impedances connected to each of said receivers, a rectifier diflerentially associated with said impedances and means for interrupting the output of said rectifier, said means comprising a Wheatstone bridge circuit having one of its resistances varied by the output of said rectifier and an interrupter connected across said bridge circuit.

-10. In a radio receiving system the combination of collecting means, a receiver resonant to signal frequency and a receiver non-lesonant to signal frequency, -i1nped-' ances connected to each of said receivers, a rectifier differentially associated with said impedancesand means for interrupting the output of said rectifier, said means comprising a \Vheatstone bridge circuit having one of its resistances consisting of athree eleci trode tube with its grid circuit associatedwith the output of said rectifier and interrupting means connected across said bridge circul HENRI JEAN JOSEPH MARIE do REGNAULD de BELLESCIZE. 

